1. Field of the Invention
The present invention relates to a bearing steel for use in ball bearings and/or roller bearings (hereinafter referred to as "rolling bearings") of engines and auxiliary equipments such as alternators driven by engines, for example, of automobiles, in particular, those used under vibration and impact load, or for use in rolling and sliding components, for example, of automobiles.
2. Prior Art
As the material for bearing rings and balls and/or rollers (hereinafter referred to as "rolling elements") in rolling bearings, high-carbon chromium bearing steels (in particular JIS SUJ2) have been used most generally and, in addition, various other materials are also used corresponding to versatile working conditions for the rolling bearings. For instance, case hardening steels (for example, SAE 5120) applied with carburizing hardening and tempering for improving the toughness are used for bearings undergoing impact loads.